Author Shu rapospectre
https://www.rapospectre.com/blog/2017-backend-interview-share
0.5 Background
Bloggers I graduated from a 2015 Communication Engineering, University of Pi 985, as they have their own business so missed the autumn senior recruit recruit college spring, a year after graduation to continue business in Beijing, but in technology start-up companies have been unable to precipitate accumulated at the end of 16 years the idea of initiation into the big corporate learning, so from the beginning of the end of 16 years of work by looking to recruit community. Although the university began to do research and development, but the frustration resume look graduate work experience, so my resume is only one year of work experience.
In this summary of an article to give you a reference;
1. Avatar title
Life should be considered first interview, starting at 11:00 am, the company is doing k12 online education related businesses, in Wudaokou there;
one side
Reception after enrollment made a pen questions, began to write, are mainly the basics of Python, not too difficult, is the basic difference between mutable objects immutable objects, subject Python garbage collection and the like, there are twelve programming that is also very simple, and finally there is a problem in accordance with the subject design data table is not difficult, to get the other two faces interviewer;
Two faces
The interviewer seems to be a director, began to let introduce themselves, he was watching my pen questions, and then ask the relevant questions some of the projects as well as simple to some system design issues based on the resume, then probably we asked pen questions in some of the issues and supplements , feeling relatively happy talk, the interviewer also more interested in my experience before, then went to inform the CTO carried out on three sides;
Three sides
The breadth and depth of the surface CTO in question are large, from knowledge to deploy server Nginx has asked some of the details, have to say to ask is quite comprehensive, the deepest impression is that this question should be:
The browser sends a request to return from experienced what speak more detailed the better
I talk about my answer:
1, starting with the network model levels:
client (browser) and server application layer protocol communication via http protocol, http protocol, http tcp-based protocol, client and server communicate mainly through socket;
Tcp and belongs to the transport layer protocol, if required take https session layer TLS, SSL and other protocols; under transport network, here is mainly OSPF routing protocol routing and forwarding, etc. and the like. And then down the data link layer is mainly ARP, RARP protocol to complete the IP address and the Mac mutual resolution, and then down to the lowest level is the physical layer basic protocols such as IEEE 802.X some bit stream into defined high and low levels of data Wait;
When the browser makes a request, the first data packet, and then resolve the IP mac address mapping data link layer, the network layer routing and upper routing table lookup to obtain the target IP address of the corresponding DNS application layer protocol, here n-hop routing pathfinding; tcp the transport layer protocol can be said that the more classic three-way handshake, the process of breaking up and four state machines, this can be put as a reference FIG:
2, aspects of the application layer:
Data exchange mainly through http protocol, the http protocol is a stateless protocol, here talk post, get differences RESTFul and interface design, the server can then talk server model epoll, select the like, then the server can tell a process flow based on actual experience ,like me:
Nginx server side to get the request, some verification, such as interception blacklist class, and then deal directly with Nginx static resource request, forwards the request to the backend server Nginx, here I use uWSGI, uwsgi agreement between them through communication, uWSGI get request may be some logic verification blacklist, determination crawlers, according wsgi standard, the parameters get environs throw Django, Django receiving a request in accordance with the standard and the env wsgi, then start startresponse, Django Related background Xianpao logic, Django get request execution of the logic within the associated request middleware, and then routed to the appropriate execution logic view, perform error exception middleware associated logic, logic response middleware then performs pre Response, Response Finally wsgi standard configuration, the need to return to get things set some headers, or cookies and the like, the last finishresponse return, then by uWSGI to Nginx, Nginx returned to the browser.
According to CTO finished talking I said, some of the details raised some questions, the last time to talk about the offer, CTO hr say go over there and talk to me directly, more surprise offer to be even higher than my own 5k . For the first time for me to find a job I was full of excitement.
Finally, talk about the environment: the company office in Wudaokou a content, scale is still relatively large, CTO listen to talk about doing things more interesting, machine learning, large data, etc. (mainly dealing with the subject of various middle and high school subjects, depth study comes to character recognition and so on, of course, I definitely want to go if business started writing), pack lunch, afternoon tea and the like others I am not quite clear, because in the afternoon left, but the company seems to classes six days a week . The company developed the feeling is still relatively high speed, interested students can try.
- Online School
The company also Wudaokou, Tsinghua science and technology park, the building opposite the former Google China office (as if there is now a move to Google)
one side
Side of the interviewer should be a back-end R & D engineers, some feel shy, I do not look at the entire process has been mainly talked resume some project experience, system design, and then asked a few simple basics of arithmetic problems and some Python, and then I went and called the two faces of the interviewer.
Two faces
Second interview the interviewer is department head, ah, this finally looked at me and chatted with me, ha ha, I feel eye contact is also very important, also asked some questions and system design experience problems because the experience is still relevant bloggers Django as relatively rich, feel they are mainly looking for business research and development, so nothing unexpected before.
Three sides
hr face, asked a number of major salary expectations, development planning and the like, mainly chat, and then send the offer.
Online school is doing Mu class platform, and is the major domestic universities and cooperation, welfare because the final did not go so it is not particularly understand, corporate environment is good.
3. Nutshell
Nutshell in the International Trade Bailang Yuan, in the innermost zone, not easy to find, go in starting a set of interview questions and a registration form, registration form and even parent families have the information, not quite understand those who want to interview information do, you do not necessarily go to your house, such as entry reloading not do it? So in addition to my information, the other I Motian. (Face so many on this husk to fill, but also fill special details, can not understand)
one side
Face questions of moderate difficulty, but more related to the surface, but also to write database queries, etc., bloggers non Coban, only about self-study database, and has been in use orm, after graduation, there is no written how the native SQL, relevant subject only by virtue of memory probably wrote down, there is a problem is to implement a stack with a complexity of O (1) of the stack and return stack max, min value of the operation, the other is that some basic Python and table design issues.
Here that problem under the Road design stack:
Access stack function O (1) no problem, mainly the max, min operation (have not seen the interview subject when bloggers looking for work, just brush some LeetCode, later found to this question is very classic, on-line a lot of answers) was not met such a demand, but certainly want to decrease the time complexity, use of space is certainly time to replace it, so there was an additional design data structure stored max min, but the design was still a problem, followed by another interviewer discuss it, or did not come to the best solution, and finally back online search found under is actually very simple, when the thin final step, interested students may have a look: stack seek min in O (1) time
Two faces
Interviewer up a pen directly ask questions to start a one, ah, even I did not let what is introduced, let alone introduce project or something, feeling a bit ignorant force, not the whole nonsense, full of a purely technical issue and algorithms , then they are good at feeling the interviewer is not interested, I'm not familiar with the questioning he was willing to, ah, two faces ignorant force, and later asked tcp traffic control, was directly wrong to say that the congestion control, the interviewer express my master tcp bad (really my problem, then go back and read it again throughout tcp).
Finally, asked a lot of the underlying database stuff, bloggers absolutely no contact, so the interviewer indicates an interviewer something (ha ha ha), and then asked me what I would like to ask, I asked two questions the interviewer expressed It still does. . . Well, then do not talk.
Summary: database knowledge is very important, even if you do not vote is to develop dba, you also have to understand the basic principle underlying database, at least to know that indexing works, MySQL database engine, and so on, because after all bloggers have hung interview database pot.
Nutshell environment looks a little messy, but relatively warm, but it is not flattered by the way the interview, so hang bloggers did not regret. Other aspects would not know it, because did not get the offer.
4.Veeva
The company also nearby World Trade Center, is a biotechnology company to (pharmaceutical companies) do crm foreign companies (but domestic and foreign parent seems nothing, is a separate subsidiary), is not the Internet company, but the salary is to force.
one side
The first is the phone interview, hr asked about the reasons for asking job-hopping, project experience, development planning, then sent homework, done after the submission;
Two faces
homework relatively simple, is a function to determine whether a leap year, but here there is a pit, when the questions were very simple, people would not IQ test, but rather look at your coding ability, engineering capabilities and object-oriented abstraction so decisive wrote a complete project, plus a complete test, and then submit it.
Three sides
hr said technical colleagues looked homework feel it is quite ok, so about the interview, the interviewer seems to come first is a leader, ask a lot of Python and Django basics and algorithm related problems, there is a white version of the scene, directly above she was out of the question, I wrote, then her review, basically LeetCode easy difficult problem, no problem.
All sides
Should be a technical Daniel, asked a question to start the system design experience, I remember is to make design a short URL generation scheme, there are some additional requirements, such as not to generate a short URL in alphabetic order, but to randomly generated, how to avoid the collision, making the most effective use of all the space.
Specific programs can be seen almost know, it has been discussed above: How short is designed link
Then end of the interview.
After the interview received a phone call saying hr technical colleagues feel good, I have no intention to ask the entry, but it was still considering Internet companies to go out so I refused. But veeva salary is to force, interested students can go and see.
5. know almost
Bloggers dream company, ha ha, go to the interview special tension. Know almost 768 creative garden, the environment is great.
one side
Side of the interviewer asked a number of project experience and start the test after personal information was mainly the interviewer a question, and then I write the code on paper, moderate difficulty, because of the relatively long interview, do not remember clearly all the questions, remember to let handwritten fast row, then Python basic knowledge, some of LeetCode questions, tcp knowledge, epoll service model, some of the principles of tornado (see ioloop can be analyzed before bloggers article tornado) database knowledge (master frankly not much) at the end of the next question binary search, one side before.
Two faces
The interviewer seems to be in charge of the commercialization of the background? Asked project experience, I asked experience, praised the entrepreneurial experience during my university, but a year after graduation venture dissatisfied (not quite understand why), and then began to ask some systems design-related topics, is deeply impressed design micro-channel architecture grab a red envelope, ah, then according to their own views, he said the algorithm point of a system and the distribution of red and attention, the interviewer should feel less satisfied. Go back and looked at the Internet, there is really write, decisive studied the situation as: micro-channel architecture design envelopes.
Later chatted for some systems design-related content, then let me and so on.
Three sides
Half an hour, to see both sides of the interviewer before and hr have been discussed, it should be not to my question, half an hour after hr chatted to chat planning and projects, and to know almost During why, then went back to reply before Friday.
This probably should not want me to determine the possibility should be used as a spare tire. Here his problem is the design of the system was not ready, on the other hand this database obviously Nutshell asked about but did not pay attention to it. Finally, the end of the year to go out looking for a job or to be careful, many large companies no point recruitment needs, unless otherwise excellent.
Finally, Friday did not receive the message, basically decided to hang up, and sure enough, when next week Monday received a rejection letter, which point to praise, there is at least a clear rejection letter, unlike some other companies, ah, I do not say so .
Know almost think it is quite awesome atmosphere, welfare is also very good, full board, do not work overtime, ah, not much to say, all the tears.
Recently a lot of know almost start to recruit people, you can try Oh, for me to complete my dream dc, ha ha ha.
6. Doctors rain
Rain doctors know almost next door, next door is really tight, the environment is also good ~
one side
As usual, introduce yourself, and then ask project experience, began to write code on paper, but here to praise the rain, face questions are very down to earth, all encoded in accordance with the actual project in question, such as doctors and patients to have a chat packet remind the subject, the subject is similar to the actual scene, there is no kind of pure arithmetic problem, then chatted for something related to Python Django basis, well into the second surface.
Two faces
Asked a number of project information and then begin the system design, remember correctly, should be to design a similar QQ chat tool, requiring the group, and can send pictures, voice and other types of messages, group administrators can manage the group and so on. He asked again later database, bluntly master database foundation is relatively small, the interviewer did not embarrass me.
Three sides
Three sides when the point of the meal in the evening, hr sister super good, take me to the outside a la carte restaurant for dinner, came back and CTO interview, exam questions Avatar CTO asked the question: a request from the browser sends to return all experienced what
So I also according to the above process spoke again, then he asked to ask their own development plans and expectations, and then I asked a few questions to ask related to rain, ending the interview.
The next day received the offer, I eat a little sister to me, ha ha, but because years ago, not for duty, only to reject out.
Generally speaking, rain environment is also very good, but I did not ask other benefits, the other slightly less clear, interested students can try.
- 360
360 Jiuxianqiao, most do not fly interview. . .
The next day the interview by direct invitation retractors morning, was already five pm. Absolutely no phone text messaging, e-mail me look ignorant to the force, I decided to call in the past confirmed, be sure to do the next day more than two hours after the car went Wangjing. (I live in Babaoshan piece)
one side
Reception allowed to enter, let notify interview people to pick, and so the moment the interviewer to pick me up, then around seven of eight around a detour did not know what to give me a pen questions, so I do not see the emphasis on the phone (did not intend bullish Well, I take the head to have a camera, you let me how to see, ha ha ha) I finished playing his phone, and then he flashed.
I look at the subject, in addition to the first three road Python is after all the basis of Linux questions, then thought: no loss is safe to do, ah, is not the same requirement, but bloggers half-level Linux only some of the commonly used commands, pen questions in the end it is his concubine usage will not do ah, then the principle of honesty finish would do a telephone call.
Two faces
Did not let the interviewer to introduce themselves, directly into the subject began to ask (my heart has produced a sense of conflict, and as husk). The first question is a Python error correction problem, the interviewer asked why such a change, I probably speak next, then the next is about lambda expressions and provides programming examples, the interviewer read nothing, followed by a two analog queue stack, write implementation code, there is not much problem, but the interviewer did not look at the code, I was asked how to achieve.
Next to the Linux part, the basic will not, will only write a simple command, the interviewer bluntly: This document questions you do is not good. How will not (I do have a question, not Linux-based, but directly in front of the rest of the denial of a little injustice ah)
Then asked a number of projects experience, to see my open source project djanog-simple-serializer ask why this is, and then I said at the sequence of solutions, the interviewer said: serialization is not very simple thing? (I did not say than done big brothers, but the other is not easy to use himself wrote a thing) and then let the interviewer asked me one forced me ten ignorant face it, as a Python people do not understand, can you give me Django and talk about simple things you can do for you? My heart was full of black question mark face, wtf? I do not know Python? Then you move Python? How the interview ah big brother, although I know other languages used to write Python 6 no problem, but we must recruit them how to write business you have to find interviews with relevant experience of it, I understand that under this section before the interview why Python I looked very official. At the moment I just want to get out, so I said, feeling recruitment needs and less consistent, do not waste time.
Well, should I be experiencing one example, please do not be prejudiced against 360.
- Today's headlines
Today's headlines in the Air Square, next to the People's University, have to say, I interviewed my nearest company, headlines the building is very domineering. Development is very rapid.
one side
The night before the interview inexplicable insomnia, is really not sleep that night, eyes open until dawn, and then forced to look ignorant to the interview, to the front desk headlines Le me go, never seen so many people to interview, to do no less than hall , and then I thought: finished, so many people, the competition is much more intense, last night insomnia, vaginal bleeding.
Sign at the front desk, took out a brand candidates, so for a while called to me, too many people in interview, the interview I really - 1st Floor cafeteria, and one side is the interviewer engineer advertising department, to introduce myself talk about business experience, asked redis usage and principle (the previous lesson a few times to ask the database, specifically bloggers fiercely looked at the basic principles of various databases), and based on my experience using the hash table is to say, raised a redis use distributed hash of potential problems, did not want to come out, to remind the interviewer about the case to the point, the main storage is possible after the problem of uneven distribution of distributed machines hash.
Then hash table asked conflict resolution programs, mainly zipper law and carry law after a chat tcp, no problem. I asked a sorting algorithm of the minimum time and complexity reasons. Then out of a series title wave that fee, requiring the calculation in constant space complexity of any fib (n) at that time may not hear, it is estimated reason did not sleep, listening to become a constant time complexity, to confirm that the interviewer is a constant time complexity (the interviewer might not hear me say, that I said spatial complexity) so think hard to no avail, the interviewer prompted dynamic programming, began to derive the transfer equation, the interviewer finally said no less complex, then one pair only to find that our understanding of the fork. it's actually really easy:
Side end of the problem, when I wrote the title of the interviewer read my blog and GitHub, expressed satisfaction with the (little surprised the first time the interviewer to see my blog and GitHub, although on a resume, but no one said read ), and then took me to one side all the problems over again, I do not know where are the complete gives the answer, never seen such a good interviewer! ! I do not know how many points they give me, I give them out!
Two faces
Two faces backstage interviewer headlines ad group in charge of my business experience is very interested and asked a lot of questions, and then see my open source project asked some questions, then raised a very interesting topic, in extreme case, the system cache all the failures, how to prevent traffic all hit the database, then consider the many ways but the interviewer did not feel very satisfied, but also be the answer to the point, and even before. After deliberately looked back to see, cache invalidation solutions, interested students search for their own "Cache reconstruction."
Then I asked a number of project-related experience and solutions out of a single list of Retrograde title (and the interviewer said the non-Coban, not a difficult subject), but then the brain is basically in a stall condition, too sleepy Finally, there is a written bug, in fact, the subject is very simple, go back down a little thought to write out:
The interviewer expressed coding capacity needs to be strengthened, then do not say he did not sleep, ability to direct that really needs to be strengthened. Interview Guan said let me go to the next round, and so the interviewer, so for a while I told the interviewer not next, felt I was hung up (the result is not really the interviewer), the interviewer like to see my the idea, repeated an interviewer really is not. Let me go back, the next interview about hr later time.
Three sides
Three sides 18:00 a week later, this time finally came to the interview room, which has a white version on three sides interviewer is leader the advertising group, come no further test basis questions, asked after experiencing a five system design problem and began to write on the white board, probably remember login management, two-dimensional code login, and so some how end design, to design a system architecture, relational database and tables, design bloggers after the interviewer spoke again, feeling the interviewer quite satisfactory, did not ask the other, directly sent for the next round of the interviewer.
All sides
The interviewer is surrounded vp headline data sector, I feel super good people, came directly told me to go to dinner, just to experience the next headline canteen, then, the fourth round of interviews is carried out at the dinner table, mainly talked about my project experience and direction as well as to why headlines last meal interviewer said this round would have been too technical examination, but it feels good to talk, do not talk technology, let me go back to other phones hr. (Headline canteen is really pretty good, but at that time did not have the nerve to play more, ha ha)
Five-sided
hr telephone chatted personal development and planning, and then determine the salaries, they made a offer ~~
Headline environment is very good, full board, cafeteria, unlimited fruit snacks as well as afternoon tea, after 10pm a taxi reimbursement, around the entry made mac, living room make up the company, the size of the Week overtime overtime, etc., in short, very much welfare (why do I know so much) recommend everyone to oh.
to sum up
Finally, bloggers chose to offer headlines. (Original interview I have found great God who, ha ha, happy)
looking for work to find this year's Festival from the end of last year, finally found a satisfactory offer, have also tangled over, feel underachievement, and even refused to go out for some time look for a job.
Many large companies are recruited from the community three years experience, so bloggers like this year's graduating recruit people to participate in society in a very awkward situation without interpolation, advise you where mentees, we must seize school trick chance ah! ! Social move to compete with your peers you do not just people.
Stumbled to find a job after a book of God "to prove safety offer" I interviewed all of the above basic problems have, recommend we must go over (to see if the earlier like, ha ha)
There are also bloggers then brush off
LeetCode
https://github.com/bluedazzle/leetcode_python
can refer to, time after bloggers have also been going to brush down.
Usually must pay attention to accumulate as much as possible to write your own conditional case some of their own projects, so the interview will be a great plus points, such as before the blogger wrote a small program: where God Hunter
https: // www. rapospectre.com/blog/create-an-onmyoji-weapp-in-24-hours
in an interview on the very good.
